1. Field of the Invention
The present invention relates to a socket connector for electrically connecting an integrated circuit package to a printed circuit board, especially to a land grid array socket connector.
2. Description of the Prior Art
Modern computer systems increase in performance and complexity at a very rapid pace, driven by intense competition and market demands. In order to meet ever-increasing performance requirements, the area and volumetric interconnect densities of electronic board assemblies must increase accordingly. In combination with other competitive forces, this demand has driven the need for improved high-density socket technologies in computer applications, and the connector industry has responded with a variety of new alternatives to meet these needs. One of the most attractive of the new connector types is the land grid array (LGA) socket connector, which permits direct electrical connection between an LGA integrated circuit and a printed circuit board. LGA socket connectors are an evolving technology in which an interconnection between mating surfaces of an IC or other area array device and a printed circuit board is provided through a conductive terminal received in the socket connector. Connection is achieved by mechanically compressing the IC onto the socket connector.
FIG. 7 discloses a conventional socket connector 90 for electrically connecting an integrated circuit (IC) package 91 to a printed circuit board (PCB, not shown). The conventional socket connector 90 comprises a plurality of conductive terminals (not shown) received in an insulative housing 94, a stiffener 95 surrounding the housing 94, a load plate 96 pivotably assembled with one end of the stiffener 95 and a load lever 97 pivotably attached to the other end of the stiffener 95.
The load plate 96 defines a pair of parallel slightly sunken pressing portions 961 and a crossbeam 962 connecting the two pressing portions 961. Each of the pressing portions 961 has an even width along a direction perpendicular to the crossbeam 962. The crossbeam 962 defines a holding portion 963 protruding therefrom.
The load lever 97 includes a pivotal section 971 and an actuating section 972 substantially perpendicular to the pivotal section 971. The pivotal section 971 defines a suppressing portion 973 extending from a middle portion thereof.
After the IC package 91 is placed in the housing 94, the load plate 96 is actuated to rotate toward the pivotal section 971 of the load lever 97, and the suppressing portion 973 is actuated by the actuating section 972 to press on the holding portion 963. Finally, the pressing portions 961 are pressed on a frame 92 of the IC package 91, which restricts the IC package 91 in the housing 94 for achieving reliable mechanical and electrical connection between the IC package 91 and the connector 90.
However, during the rotation process of the load plate 96, the pressing portions 961 firstly press on the marginal part of the frame 92 of the IC package 91, and gradually press on the middle part of the frame 92. While the pressing portions 961 press on the marginal part of the frame 92, the pressing force will tilt the IC package rotatably about the pressing point. Along with the rotation process of the load plate, the pressing portions press on the middle part of the frame 92, and the IC package is pressed down, which makes it easy for the IC package to slide relative to the housing 94 and scrape on the housing 94. And as a result, the IC package 91 cannot align with the terminals received in the housing 94, and the housing 94 is abraded.
Hence, a new socket connector which overcomes the above-described disadvantages is desired.